The present invention relates to a cosmetic treatment of hair, in particular highlighting, and an implement for carrying out the treatment.
Hair highlighting has been one of the mainstays of the professional salon industry. In this process, strands of hair are typically segregated from the remainder and treated with a composition comprising peroxides and/or persulfates. The technical skill required to separate the target hair and mix and apply decolorizing products to only those areas has kept this procedure mostly in the purview of hair salons. Traditionally, the segregation of hair was done by applying a plastic cap over the head and drawing small sections of hair through it. More commonly now, hair is selected through weaving and then placed onto metallic foils (usually aluminum foil) that are then painted with the highlighting composition. This allows for smaller, more independent sections to be treated, resulting in a more natural highlighted look. Although the effect is visually more appealing, these procedures are time consuming and generally require the skill of a professional haircolorist. Salons charge accordingly—often in excess of 100 USD per service.
Some highlighting services, especially on clients with lighter haircolor or those who desire less contrast in their highlights, are performed using oxidative haircolor techniques and products. These are performed using oxidative haircolor tints that have little or no oxidative dye precursors and are alkalized with relatively high levels of common hair dye alkalizers (generally, but not limited to, ammonium hydroxide and monoethanolamine). These are combined at the time of the service with high-volume peroxide developers to form an unstable highly alkalized peroxide composition that can effectively decolorize hair to a limited extent. By “high volume peroxide developer” we mean, as generally understood in the art of hairdressing, an aqueous peroxide solution, suspension, or emulsion that contains hydrogen peroxide in an amount greater than 30 volume (approximately 9.0% w/w). Higher levels of oxidative dye precursors (couplers and developers) in addition to the alkilizing agent may also be used if a further coloring effect is desired. In this case, the highlighted strands of hair will be at least partially colored by the oxidative dyes in addition to losing its natural shade due to the destruction of the natural pigments of hair (melanin) by the oxidizing agent. Therefore for the purpose of this application, the term “highlighting” encompasses “bleaching only” treatment and “bleaching plus dyeing” treatment (also referred to in the art as “permanent dyeing” or “permanent coloring”).
Commonly, hair salons use high lift powdered bleaches for highlighting effects. High lift bleaches, using combinations of sodium, potassium, and ammonium persulfate along with hydrogen peroxide at elevated pH, provide fast decolorizaion with an acceptable amount of hair damage. Up to seven levels of lift are possible using a single application of some off-the-scalp bleaches. These are difficult to use due to the need to combine the persulfate mixture with the peroxide immediately prior to use. The high volume peroxide may be irritating to skin and mucous membranes. The persulfate powders are dusty and can be irritating if inhaled. This procedure is also limited by the technology in that the metallic foils need to be opened periodically to determine the degree of decoloration. Thus despite the high demand for these effects, high lift treatments are relegated to a small corner of the at-home consumer market.
Hydrogen peroxide solutions have been formulated into hair lightening products for consumer use. Products such as Sun In (RTM), A Touch of Sun (RTM), and most recently Salon Selectives Lighten Up Highlighting Mousse (RTM) have been introduced to give consumers a gradual highlighting effect. Hydrogen peroxide is unstable for storage at elevated pH (generally greater than pH 4.0) and the decolorizing effect of it at low pH is relatively weak. Therefore multiple applications of low pH products applied repeatedly over time are required to achieve a desired lightening effect. Further, these are whole-head lightening effects. Further examples of bleaching compositions are disclosed in U.S. Pat. No. 5,888,484 and U.S. Pat. No. 5,888,249.
As discussed above, highlighting usually involves mixing a first composition comprising an oxidizing agent and a second composition comprising an alkalizing agent and optionally oxidative dye precursors. The mixed composition should be carefully applied on the strands of hair to be treated so that it does not spread to adjacent sections of hair. In addition to the aluminum foil discussed above, various systems have been proposed for making sure that the composition remains on the strands of hair to be treated.
In U.S. Pat. No. 2,655,924 the strands of hair to be treated are pulled inside a tube using a hooked needle. A dyeing or bleaching composition is subsequently poured inside the tube, which is then sealed for the duration of the treatment.
U.S. Pat. No. 2,819,721 discloses another method of dyeing or bleaching hair wherein the hair to be treated is drawn in a first tube of deformable liquid-impervious material. The strands of hair are pulled inside the first tube of deformable material using a second tube movable within the first and having a jaw mechanism that can be actuated by the consumer. The first tube is subsequently filled with the treating composition.
U.S. Pat. No. 5,146,937 discloses the use of a sheet made of polymer material, preferably polystyrene, as a dye-applying pad for hair highlighting. The polystyrene sheet defines one and another opposite flat portions merging about a fold line. A lock of hair is laid over one flat half portion of the sheet, and a fluid dye solution including oxidizing means is applied to the lock of hair. The other flat half portion of the sheet is then folded over and flatly compressed against the first portion of sheet to take the locks in a sandwich for a sufficient development time to enable permanent hair coloring.
All these methods require the consumer to apply a fluid reactive composition to the hair to be treated, which can be messy and may require specialist training.
U.S. Pat. No. 5,845,653 and U.S. Pat. No. 5,931,168 disclose an applicator for transferring color-altering material from a rigid substrate to hair or fibers. The applicator includes a color-altering dye powder material soluble in water and/or water-activated which is affixed to at least one side of the applicator. The applicator is folded around the strands of hair to be treated and is activated by wetting either the hair or the applicator itself before use. These documents only consider applicators including one type of composition. Furthermore only powdered or particulate dyeing agents are considered.
U.S. 5,891,453 and 5,879,691 teach the use of strips of clear plastic coated with a hydrogen peroxide gel comprising a carbopol resin to whiten teeth.
U.S. 5,116,388 teaches the use of persulfate compositions enclosed in PVA packettes and their use in hair bleaching.